Method and apparatus for installing a permeable well liner



p 6, 1966 J. PAPAILA 3,270,817

METHOD AND APPARATUS FOR INSTALLING A PERMEABLE WELL LINER Filed March26, 1964 INVENTOR. JOH/V PAPA/4 ATTOENETY.

United States Patent 3,270,817 METHOD AND APPARATUS FOR INSTALLING APERMEABLE WELL LINER John Papaila, Kiskiminetas Township, ArmstrongCounty,

Pa., assignor to Gulf Research & Development Company, Pittsburgh, Pa., acorporation of Delaware Filed Mar. 26, 1964, Ser. No. 354,837 9 Claims.(Cl. 166-46) This invention relates to a method and an apparatus forpreventing the movement into a well bore of individual particlescomprising an unconsolidated rock formation.

Many underground rock formations are unconsolidated or so poorlyconsolidated that they readily disintegrate under the forces exertedupon them by the flow of formation fluids into a well bore penetratingthe formation. Such rock formations are hereinafter referred togenerally as unconsolidated formations. It has been found that whenfluids flow from unconsolidated formations into a well bore, thedisplacement of formation particles into the well bore permits themovement of additional particles farther back in the formation andresults in plugging of the well bore and of the formation flow channelsaround the well bore. To prevent the rearrangement of the formationparticles under the forces of fluid flow, it is necessary to preventsubstantially the movement of formation particles into the well bore. Itis possible to assure the substantially complete prevention of themovement of individual formation particles around or into the well boreby continually exerting a force outwardly from the well bore upon thewall of the well bore. Such force should be approximately equal to theforce exerted upon the unconsolidated formation by the weight of theoverbearing rock formations.

Various methods and types of apparatus have been suggested foralleviating the problems involved in producing fluids from a well borepenetrating an unconsolidated formation, among which is the setting ofscreens or slotted liners in the well bore adjacent the formation. Suchdevices frequently are not entirely satisfactory because the slightmovement of sand from the formation into the annulus of the well borearound the slot-ted liner or screen often results in plugging of theformation around the well bore and requires a work over operation torestore the well to production. Gravel packing of the annulus formed bythe wall of the well bore around a liner has also been suggested, butthat method is expensive, involves a considerable amount of rig time anddoes not always prevent plugging of the formation around the well bore.

It is an object of this invention to provide a means whereby a springsupported expansible permeable liner can be set in a well borepenetrating a formation without substantial damage to the liner.

This invention resides in a method and an apparatus for arresting themovement of formation particles around a well bore penetrating anunconsolidated rock formation by setting in the well bore an expansiblepermeable liner containing a helical spring whereby the liner isforcibly urged against the wall of the well bore. The apparatus of thisinvention comprises a setting tool suitable for maintaining the springand liner in a stressed condition while the liner and spring are beingrun in the well bore. The setting tool is so designed that, when theliner and spring are in position in the well bore, the setting toolfirst reduces the elongating force on the spring and then reduces thetorsional force. When the tensional stress in the spring issubstantially released before the torsional stress is reduced, theforces acting to expand the liner into contact with the wall of the wellbore are not exerted completely until the torsional stress in the springis substantially released. Such a gradual relaxation of stresses in thespring produces a gradual expansion of the liner which prevents tearingof the liner as the liner engages the wall of the well bore.

The construction and operation of the apparatus of this invention can beexplained with reference to the accompanying drawings wherein:

FIGURE 1 is a vertical cross-sectional view of an expansible permeableliner and its supporting springs secured in a stressed condition on thesetting tool of this invention.

FIGURE 2 is a plan view of the top of the setting tool with the linersprings attached.

FIGURE 3 is a plan view of the bottom of the setting tool with the linersprings attached.

Referring to FIGURE 1, a Well bore 2 is shown penetrating anunconsolidated subterranean rock formation 3. The bottom of a string ofwell casing 4 rests on an inwardly extending shoulder 5 in well bore 2.Casing 4 is secured to the wall of well bore 2 by a sheath of cement 6.An inwardly extending shoulder 7 at the bottom of casing 4 engages theupper end of a rigid liner support 8. A snap ring 9 secures the upperend of an expansible permeable tubular liner 10 to the bottom of linersupport 8. The setting tool, indicated generally by reference numeral12, is shown with liner 10, liner support 8, and two interwoven helicalliner springs 14 and 16 secured to the setting tool 12 in the stressedcondition employed when the apparatus is suspended from a wire liner 18and run in the well bore 2.

The setting tool 12 comprises a cylinder 20 forming therein a torquepressure chamber 22 and an elongation pressure chamber 24 which areseparated by a transverse wall 27. A bushing 28 is threadably connectedto the upper end of cylinder 20 and partially closes the upper end ofchamber 22. A torque piston 26 is incased in chamber 22, and a fluidseal between the side of piston 26 and the wall of chamber 22 iseffected by an O-ring 30 set in a groove 32 cut around the circumferenceof piston 26. Piston 26 extends from the lower end of a threaded shaft34 which passes through the threaded central passage of bushing 28. Themating threads of shaft 34 and bushing 28 are both low-pitch, coarsethreads to minimize the force required to turn shaft 34 in bushing 28.

Extending from the upper end of shaft 34 is a valve housing 38 connectedto the lower end of wire line 18 and containing an upper pressuringvalve 40 and an upper pressure release valve 42. Pressure release valve42 is actuated by suitable means such as an automatic timing mechanism43, a solenoid (not shown in the drawing), or a detonating cap (notshown). A lateral fluid passage 44 extends through valve housing 38between pressuring valve 4% and pressure release valve 42. An upperlongitudinal fluid passage 46 communicates with lateral fluid passage 44and extends downwardly through shaft 34 and piston 26 and opens intochamber 22.

A circular disc 48 extends radially from the upper end of shaft 34 belowvalve housing 38. The diameter of disc 48 is slightly larger than theexternal diameter of cylinder 20. An upper cylindrical tool sleeve 50extends from the circumference of disc 48 downwardly around cylinder 20for approximately the length of shaft 34. The internal diameter of toolsleeve 50 is slightly larger than the external diameter of cylinder 20to permit the unrestricted movement of tool sleeve 50 around cylinder 20as shaft 34 is rotated in bushing 28. Two spring stays 52 extend fromthe edge of disc 48 to secure the ends of springs 14 and 16 as indicatedin FIGURE 2. The spring stays 52, positioned diametrically opposite eachother on the circumference of disc 48, engage the ends of springs 14 and16 to impart a torsional force to springs 14 and 16 when the springs arewound and to secure springs 14 and 16 to the upper end of setting tool12 until they unwind.

An elongation piston 54 is sidably incased within hamber 24 and a fluidseal between piston 54 and the wall of chamber 24 is provided by anO-ring 56 set in a groove 58 cut around the circumference of piston 54.A cylinder collar 60, threadably connected to the lower end of cylinderhas an inwardly extending shoulder 62 to limit downward movement ofpiston 54 in chamber 24. A piston shaft 64, having a non-roundcross-section, extends from the bottom of piston 54 downwardly through asimilarly shaped central passage 66 in collar 60. The seating of shaft64 in passage 66 prevents the turning of shaft 64. A circular base plate68, extending radially from the lower end of shaft 64, has a diameterslightly larger than the external diameter of cylinder 20. A lowercylindrical tool sleeve 70 extends upwardly from the circumference ofbase plate 68 and slides along the outer surface of cylinder 20 as shaft64 moves through passage 66 in collar 60. Spring latches 72 arepivotally connected at 74 to base plate 68 as indicated in FIGURES 1 and3. The lower ends of springs 14 and 16 are secured to spring latches 72as shown in FIGURE 3, and the upward rotation of latches 72 past aposition that is parallel to the bottom of base plate 68 is prevented bythe seating of latches 72 against the surfaces 76 of base plate 68.

A lower valve housing 78, extending downwardly from the bottom of baseplate 68, contains an elongation pressuring valve 80 and an elongationpressure release valve 82. Pressure release valve 82 is actuated bysuitable means such as an automatic timing mechanism 83, a sole noid(not shown in the drawing), or a detonation cap (not shown). A lateralfluid passage 84 connects valves 80 and 82 with a longitudinal fluidpassage 86 extending through shaft 64 and piston 54 and opening intochamber 24.

The lower end of liner 10 is secured, as indicated in FIGURE 1, around arigid retaining ring 88. The retaining ring 88 has a diameter less thanthe diameter of base plate 68 and prevents upward movement of liner 10around setting tool 12 while the tool and liner are being loweredthrough well bore 2. At the upper end of the apparatus, a ribbed disc 90is secured within a groove 92 in the wall of liner support 8. The disc90 is shaped like a spoked wheel and fits around wire line 18 to seat ontop of valve housing 38 to prevent movement of liner 10 and linersupport 8 downwardly around setting tool 12 as the tool and linerassembly are lowered through well bore 2. The disc 90 is made of afrangible or deformable material that can be unseated from groove 92 byupward tension applied to wire line 18 and thereby permits the removalof setting tool 12 from the well bore 2 after liner 10 and liner support8 are set therein.

When the method and apparatus of this invention are employed to arrestthe movement of unconsolidated formation particles into a well bore 2penetrating the formation, the following procedure can be used. A singlehelical spring can be employed to support the liner in the well bore 2according to the method of this invention. However two interwovenhelical springs 14 and 16 have been described in the embodiment of theinvention set forth in the specification because the use of two springsinstead of one imparts less motion and less stress to the expansibleliner 10 when the liner 10 and springs 14 and 16 are released in theWell bore 2, thereby reducing the possibility of damaging the liner 10while setting it. The interwoven springs 14 and 16 are slipped over thesetting tool 12 and the tool 12 and springs 14 and 16 are elongated bypumping a liquid through pressuring valve 80 in valve housing 78. Whilethe springs 14 and 16 are being elongated, care must be taken that theends of springs 14 and 16 remain engaged by spring latches 72 at thelower end of springs 14 and 16 and by the spring stays 52 at the upperend of springs 14 and 16. When the fluid pressure in chamber 24 hasforced the piston 54 into contact with the inwardly projecting shoulders62 of collar 60, the injection of liquid through pressuring valve 80 ishalted.

Then liquid is injected into pressuring valve 40 in valve housing 38 atthe upper end of setting tool 12. Whilev liquid is being injectedthrough valve 40 and fluid passage 46 into pressure chamber 22, the disc48 is rotated to impart a torsional stress to the springs 14 and 16.Without the upward force exerted upon shaft 34 by the action of thefluid pressure in chamber 22 upon piston 26, the restoring force of thesprings 14 and 16 would be adequate to rotate the disc 48 and unwindsprings 14 and 16. Howi ever, when a sufiicient pressure is attained inchamber 22, the upward force exerted upon piston 26, and therebytransmitted to shaft 34, prevents the recession of piston 26 and shaft34 into chamber 22 and thereby prevents the restoring forces exerted bysprings 14 and 16 from rotating disc 48 to unwind the springs.

After the forces of elongation and torsion are applied to springs 14 and16, the expansible permeable tubular liner 10 is stretched over thesprings 14 and 16 and mounted on setting tool 12. Alternatively, theliner 10 and springs 14 and 16 can be mounted on the tool 12 Isimultaneously before the stresses are applied to springs 14 and 16. Theexpansible permeable liner 10 may be made from any material that resistscorrosion from the formation fluids and is sufiiciently deformable toconform to the variations in the diameter, of the well bore over theinterval of the unconsolidated formation. Thus the liner 10 can comprisea tube of nylon or chemically treated rubber. Such a liner might fitsmoothly around springs 14 and 16, or it might be pleated or convolutedto allow for greater expansion. can comprise a thinwalled tube of sheetmetal such as steel, copper, or brass. Such a liner can consist of acontinuous, substantially cylindrical metal sheet or a wound sheet withoverlapping ends. A metallic liner can be made of either smooth orcorrugated metal. If the material of the expansible liner 10 is notnaturally permeable, it can be rendered permeable by cutting slits inthe liner or by perforating the liner wall and setting in eachperforation a permeable sand barrier or cloth or a fine mesh screen.

The liner support 8 can be constructed of any rigid material such asmetal or plastic that is resistant to corrosion by the formation fluidsand can comprise any suitable means for securing liner 10 to the lowerend of easing 4. In a preferred embodiment of this invention, the upperend of liner 10 is secured to the lower end of liner support 8 by themetallic snap ring 9. The preceding descriptions of the liner 10 andliner support 8 are' not intended as exclusive of other embodiments ofthe apparatus of this invention but are presented merely by way ofillustration.

After liner 10 is mounted on setting tool 12, the timing mechanisms 43and 83 on pressure release valves 42 and 82 are set to assure that valve82 is actuated a substantial period of time before valve 42. In thealternative,

det-onating caps or solenoids can be attached to actuatevalves 42 and 82and can be connected by suitable electric leads to an energizing sourceat the surface. After the pressure release valve release mechanisms areset, the setting t ol 12 with springs 14 and 16, liner 10, and

liner support 8 secured are lowered through the well bore to the levelof the unconsolidated formation.

According to the method of this invention pressure release valve 82 isactuated first and permits the gradual bleeding off of the pressureliquid contained in chamber 24. Such a release of the pressure exertedon piston 54 forces of springs 14 and 16 are then capable of rotatingAlternatively, liner 10- disc 48, thereby reducing the torsional stresson springs 14 and 16. As springs 14 and 16 unwind and the diameter ofthe springs increases, springs 14 and 16 and the expansible well boreliner forcibly engage the wall of the well bore in substantialconformity with the contours of the wall. Because the release of theliquids from chambers 22 and 24 is controlled to allow for a gradualreduction in the forces exerted on pistons 26 and 54, the release of thestresses in springs 1-4 and 16 does not occur substantiallyinstantaneously but rather is reduced gradually to prevent damage to theliner 10 as it comes into contact with the wall of the well bore 2. Asthe torsional stresses in springs 14 and 16 are reduced and the diameterof the springs increases, the upper and lower ends of springs 14 and 16disengage from spring stays 52 and spring latches 72 to permit thesubsequent release and removal of setting tool 12 from well bore 2 afterthe liner 10 and springs 1-4 and 16 have engaged the wall of Well bore2.

The preceding description discloses a method and an apparatus forsetting an expansible liner in a well bore penetrating an unconsolidatedformation. The invention disclosed herein has many advantages over themethods and apparatus heretofore suggested for supporting a well bore inan unconsolidated formation. For example, the method by which the tooloperates to set the liner in the well bore by first gradually reducingthe elongation of the spring and subsequently gradually releasing thetorsion in the spring prevents damage to the liner and assures asubstantial conformance of the shape of the set liner to the contours ofthe wall of the well bore. Another advantage provided by the method andapparatus of this invention is that the forceable engagement of theliner with the wall of the Well bore in conformity with theirregularities therein assures substantially complete prevention of themovement of individual formation particles around or into the well bore.Thus, plugging of the unconsolidated formation some distance away fromthe well bore owing to rearrangement of the formation particles isprevented.

Although the foregoing specification has described the use of theapparatus of this invention in an open well bore, the apparatus andprocedures set forth can also be used to set an expansible liner in acased or cemented well bore. Such an embodiment of this invention can beemployed to set an impermeable liner in a well bore to seal off aleaking joint of casing or a poorly cemented section of the well bore.While the preceding specification has described a single embodiment ofthis invention in considerable detail, it is obvious that others skilledin the art can device and build alternate and equivalent devices whichare within the scope and spirit of this invention. Therefore it isdesired that the protection afforded this invention be limited not bythe constructions illustrated and described herein but only by theproper scope of the appended claims.

Therefore I claim:

1. A method for arresting the movement of formation particle-s around awell bore penetrating an unconsolidated formation comprising insertingin the well bore at the level of the formation an expansible permeabletubular liner, inserting with the liner into the well bore controllablemeans to expand the liner; said means constricted by tensional andtorsional stresses when said means are inserted in the well bore topermit the passage of said means and liner through the Well bore,positioning the liner and said means in the Well bore adjacent theformation, first gradually releasing the tensional stress in said means,then gradually releasing the torsional stress in said means, therebyexpanding said means and urging the liner into forceable engagement withthe wall of the well bore in substantial conformity with the contours ofsaid well bore.

2. A method for arresting the movement of formation particles around awell bore penetrating an unconsolidated formation comprising insertingin the well bore at the level of the formation an expansible, permeabletubular liner having extending therethrough a helical spring subjectedto both tensional and torsional forces which oonstrict the spring andreduce its diameter sufficiently to permit the passage of the spring andliner through the well bore, positioning the spring and liner adjacentthe unconsolidated formation, first releasing the tensional forces,exerted upon the spring to shorten the spring and increase its diameter,then releasing the torsional force exerted upon the spring to expand thediameter of the spring, thereby urging the liner to forceably engage thewall of the well bore in substantial conformity with the contours ofsaid well bore.

3. A method for arresting the movement of formation particles around awell bore penetrating an unconsolidated formation comprising insertingin the Well bore at the level of the formation an expansible permeabletubular liner containing a helical spring subjected to both tensionaland torsional forces to const-rict the spring and reduce its diametersufi'iciently to permit the passage of the spring and liner through thewell bore, positioning the spring and liner in the Well bore adjacentthe formation, first gradually releasing the tensional force exertedupon the spring to shorten the spring and increase its diameter,subsequently gradually releasing the torsional force exerted upon thespring to farther expand the diameter of the spring and thereby urge theliner to forceably engage the wall of the well bore in substantialconformity with the contours of the well bore.

4. In a method for arresting the movement of formation particles arounda well bore penetrating an unconsolidated formation by forceably urgingagainst the wall of the well bore an expansible permeable tubular linercontaining a helical spring which has been constricted by the impositionin. the spring of tensional and torsional stresses to allow the passageof the spring and liner through the well bore, the improvementcomprising the setting of the spring and liner in the well bore adjacentthe formation by first releasing the tensional stress in the spring,then releasing the torsional stress in the spring to increase thediameter of the spring and urge the liner into forceable engagement withthe wall of the well bore in substantial conformity with the contours ofthe well bore.

5. A tool for inserting and setting in a well bore an expansiblepermeable liner mounted on said tool around a helical spring comprisingfirst means to impart a tensional stress to said spring, second means toimpart a torsional stress to said spring, third means for graduallyreleasing the tensional and torsional stresses whereby the spring andliner are urged into forceable engagement with the Wall of the wellbore, and control means adapted to assure that the tensional stress issubstantially released before the torsional stress is reduced.

6. A tool for inserting and setting in a well bore an expansiblepermeable liner containing a spring to urge the liner into forceableengagement with the wall of the well bore, said tool comprising a firstcylinder-piston unit having means to secure the spring to one end of thetool and to sustain a torsional stress in the spring while the tool isbeing run in the well bore, a second cylinderpiston unit having means tosecure the spring to the other end of the tool and to impart a tensionalstress to the spring and sustain said tensional stress while the springis being run in the well bore, and means whereby first the tensionalstress is substantially released and thereafter the torsional stress isreleased to free the spring from the tool, thereby permitting removal of[the tool from the well bore after the spring and liner have been settherein.

7. Apparatus for arresting the movement of formation particles around awell bore penetrating an unconsolidated formation comprising a string ofwell casing secured to the Wall of the well bore and extending thereinfrom the surface to a depth slightly above the top of the formation, asetting tool suspended on a steel cable Within the well bore adjacentthe formation below the lower end of the casing, an expansible permeabletubular liner containing a helical spring and detachably mounted withthe spring on the setting tool, rigid liner supporting means connectedto the upper end of the liner and adapted to engage the lower end of thecasing above the formation, said setting tool having means to imparttensional and torsional stresses to said spring, said setting tool alsohaving controllable means for gradually releasing first the tensional,and thereafter the torsional, stresses in said spring whereby the springand liner are disengaged from the setting tool and are urged intoforceable engagement with the wall of the well bore.

8. A tool for inserting and setting in a well bore an expansiblepermeable tubular liner containing a helical spring to urge said linerinto forceable engagement with the wall of the well bore, said toolcomprising a cylinder forming separate first and second pressurechambers therein, an upper closure means connected to the upper end ofsaid cylinder, said closure means having a threaded passagetherethrough, a threaded cylindrical shaft rotatably secured in thepassage through said upper closure means, an upper piston mounted on thebottom of the threaded shaft and slidably incased in the first chamber,means extending from the upper end of said threaded shaft and engagingthe upper end of the spring, means to impart fluid pressure to the firstchamber and the upper piston whereby motion of the threaded shaftthrough the upper closure means is prevented, lower closure meansconnected to the lower end of the cylinder, a non-round passageextending through said lower closure means, a non-round shaft slidablein the passage through the lower closure means, a lower piston mountedon the upper end of said non-round shaft and slidably incased in thesecond cham ber, means extending from the lower end of the non roundshaft to secure the lower end of the spring to the tool, means to impartfluid pressure to the second chamber and the lower piston to move thelower piston downwardly and thereby elongate the spring, and means toprovide for the controlled gradual release of fluid pressure from thesecond chamber and thereafter from the first chamber whereby the linerand spring are released from the tool and forceably engage the wall ofthe well bore in substantial conformity with the contours thereof.

9. A setting tool for inserting and setting in a well bore an expansiblepermeable tubular liner mounted on said tool around a plurality ofinterwoven helical springs, said tool suspended on a steel cable in thewell bore and comprising a cylinder having upper and lower pressurechambers therein, a bushing threadably connected to the upper end of thecylinder, a central threaded passage through said bushing, a rotatablethreaded shaft extending through said central passage, an upper pistonextending from the lower end of the threaded shaft and slidably incasedin the upper chamber, means at the upper end of the threaded shaftadapted to engage the upper ends of the springs and secure the springsto the tool, means to impart a fluid pressure to the upper chamber andpiston whereby rotation of the threaded shaft in the bushing isprevented, a

collar connected to the lower end of the cylinder and having an inwardlyextending shoulder, a non-round passage extending through the shoulder,a non-round shaft slidable in the non-round passage, a lower pistonextending from the top of the non-round shaft and slidably incased inthe lower chamber, a disc mounted on the lower end of said non-roundshaft, a plurality of rigid spring latches pivotally connected to saiddisc and extending radially therefrom to engage the lower ends of thesprings and secure the springs to the tool, means to impart a fluidpressure to the lower chamber and piston whereby the springs areelongated, and timing means to effect the gradual release of fluidpressure first from the lower chamber and thereafter from the upperchamber whereby the springs are disengaged from the tool and urge theliner to engage the wall of the well bore in substantial conformity withthe contours thereof.

References Cited by the Examiner UNITED STATES PATENTS 2,138,156 11/1938Halliburton l66l79 X 2,812,025 11/1957 Teague et a1 166207 2,833,3525/1958 Lloyd 166227 X 3,067,819 12/1962 Gore 16648 CHARLES E. OCONNELL,Primary Examiner.

D. H. BROWN, Assistant Examiner.

3. A METHOD FOR ARRESTING THE MOVEMENT OF FORMATION PARTICLES AROUND AWELL BORE PENETRATING AN UNCONSOLIDATED FORMATION COMPRISING INSERTINGIN THE WELL BORE AT THE LEVEL OF THE FORMATION AN EXPANSIBLE PERMEABLETUBULAR LINER CONTAINING A HELICAL SPRING SUBJECTED TO BE TENSIONAL ANDTORSIONAL FORCES TO CONSTRICT THE SPRING REDUCE ITS DIAMETERSUFFICIENTLY TO PERMIT THE PASSAGE THE SPRING AND LINER THROUGH THE WELLBORE, POSITION THE SPRING AND LINER IN THE WELL BORE ADJACENT THE FORM